Cast aluminum frame for a power operated lawn mower



April 6, 1955 JEPsoN E'rAl.. 3,176,454

CAST ALUMINUM FRAME FOR A POWER OPERATED LAWN MOWER Original Filed Nov.12, 1958 8 Sheets-Sheet 1 INVENTORS. /1442 L/.s-Pso/x/ BY No ErcfJ/so/vCLL/LL en-3e Cefa/'n April 6, 1965 l. JEPsoN ETAL CAST ALUMINUM FRAMEFOR A POWER OPERATED LAWN MOWER Original Filed Nov. l2, 1958 8Sheets-Sheet 2 @n @m a 1. mmm mw bmw QS g lll llllll 'mnu Je (Yala/5ArrozA/evf.

April 6, 1965 l. JEPsoN ETAL CAST ALUMINUM FRAME FOR A POWER OPERATEDLAWN MOWER Original Filed Nov. 12, 1958 April 6, 1965 l. JEPsoN E'rAl.3,176,454

CAST. ALUMINUM FRAME FOR A POWER OPERATED LAWN MOWER original Filed Nov.12. 195e s sheets-Sheet 4 :y INVENTORS.

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April 6, 1965 l. JEPsoN ETAL CAST ALUMINUM FRAME FOR A POWER OPERATEDLAWN MOWER 8 Sheets-Sheet 5 Original Filed Nov. l2, 1958 m g INVENTORS.\O

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April 6, 1965 l. JEPsoN ETAL CAST ALUMINUM FRAME FOR A POWER OPERATEDLAWN` MOWER Original Filed Nov. 12, 1958 April 6 1965 l. JEPsoN ETALCAST ALUMINUM FRAME FOR A POWER OPERATED LAWN MOWER Original Filed Nov.12, 1958 8 Sheets-Sheet 7 INVENTORS.

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3,176,454 CAST ALUMINUM FE FOR APWER K, OPERATED LAWN MWER Ivar Jepson,Oak Park, Ill., and Etchison G. Lili, East Lansing, Mich., assignors toSunbeam Corporation, Chiy icagmlil., a corporation of Illinois Originalapplication Nov. 12, 1958, Ser. No. 773,456, now Patent No. 3,035,386,dated May 22, 1952. Divided and this application Sept. 18, 1961, Ser.No. 133,649 Claims. (Cl. 56-249) The present invention relates to lawnmowers, and more specifically to power lawn mowers of they type in whicha suitable 'prime mover is associated with the lawn mower to drive thecutting mechanism and, if desired, to propel the lawn mower over thearea to be mowed. Specifically,

ylawn mower, the latter being a lawn mower in which a blade generallyparallel with the surface to be mowed is driven at high speed by asuitable prime mover. These power lawn mowers have principally usedelectric motors and internal combustion engines as the source of power,for driving the cutting mechanism, and in many cases forpalsopropelling the mower over the lawn or surface to be cut. In recent yearsthe electric powered lawn mower has become quite popular. It has a greatadvantage over a mower powered by an internal combustion engine lfromythe standpoint of noise and also from the standpointfof the ease withwhich the prime mover can be started and stopped. The disadvantage ofthe lawn mower powered with an electric motor has been the so-calledcord problem. In recent years people have learned how to use a poweroperated lawn mower powered by an electric motor so that the heretoforeexisting cord problem is nor longer considerved a problem. In JepsonPatent No. 2,926,478 assigned to the same assignee as the instantapplication, there is disclosed and claimed a power operated lawn mowerin which an electric motor is the prime mover for driving the cuttingmechanism. This lawn mower has gone into extensive commercial use andhas proved to be very popular and unusually successful. The lawn mowerdisclosed in that patent is of the rotary type. It would be desirable toprovide a power operated lawn mower of the reel type which is assuccessful as the power operated rotary mower disclosed and claimed inthe above-mentioned patent. For certain types of grass, notably theso-called creeping bent type of grass, a reel type lawn mower issuperior to a rotary type cutting device. In addition to that, there arenumerous householders who feel that reel type lawn mowers are lessdangerous than rotary type lawn mowers. Whether or not this is reallytrue is questionable, but it is Well settled that there is a greatdemand for a satisfactory power operated reel type lawn mower which issimple and compact and light in weight so that it can be usedsatisfactorily by one who has only a relatively small lawn to mow.

Lawn mowers of the reel type comprise a rotatable reel having usually aplurality of blades which move into shearing engagement with ahorizontally disposed cutter bar, which cutter bar moves over the lawnat a height which determines the height of cut. The reel and cutter barare supported on a frame usually comprising end United States PatentMice airain Patented Apr. @A6, 1965 plates connected together by one ormore crossbars, and the reel is commonly journaled in the end plates.With such an arrangement relative movement between the reel and cutterbar is necessary to control a close shearing action. In some lawn mowersthe reel is mounted in a fixed position in the end plates and the cutterbar i's adjustable to a limited extent to keep it in good shearingengagement with the reel. In other lawn mowers of this type the cutterbar is fixed and the reel is mounted on an eccentric or the like so thatit may be adjustable relative to the cutter bar. The present inventionis .primarily concerned with a reel type lawn mower in which the cutterbar is essentially fixed to the frame and the reel is adjustablerelative to the xed cutter bar.

It will be appreciated that in a reel type lawn mower good cuttingaction is assured only if the reel and cutter bar make proper shearingvcontact throughout theentire length of the reel and cutter bar. Duringthe cutting of a lawn where the grass is thick and the growth is heavy,the wedging action of the grass between the cutter bar the reel tends todeflect the center portion of the cutter bar, which is the leastSupported portion. Obviously, if deflection of the center of the cutterbar occurs, poor cutting or shearing action will result. For this reasoncutter bars have been built so as to be supported on a heavy frame whichcannot distort. Generally when mowing a lawn, successive paths of themower are taken so that a slight overlap occurs, which means that theend portions of the cutter bar do less cutting action than the centralportion which is always cutting grass. Consequently, there i's more wearof the central portion of the cutter bar. Even aside from the wearfactor of the center portion of the cutter bar due to cutting more grassat that portion, there is also the problem caused by vibration. Thecenter of the cutter bar is the least wellsupported portion thereof, andif the resonant frequency of the cutter bar is close to the frequencywith which the blades pass the cutter bar there is the possibility ofexcessive and uneven wear of the cutter bar. Thus there is anotherreason for making the cutter bar rigid so that its resonant frequency ofVibration is high relative to the speed of the reel. Unfortunately, whenone increases the strength and rigidity of the cutter bar or cutter barsupport to avoid the factors enumerated above, the weight of the mowerincreases and from the householders standpoint this is very undesirable.In general, although a lawn mower is power driven, there still is aconsiderable amount of hand manipulation necessary to guide the mowerand the like, particularly when the lawn to be mowed has numerous trees,bushes, Vshrubbery and the like. Consequently, it would be desirable toprovide a power operated lawn mower of the reel type provided with acutter bar which has the features of a rigid, heavy cutter bar withoutthe increased weight.

In any reel type lawn mower the effectiveness thereof is determined bymaintaining the cutter bar landrreel in y constant shearing engagementthroughout the 'entire length thereof. With a heavy reel, a very rigidframe and a very rigid cutter bar this can be accomplished, but a heavylawn mower results. It would be desirable to provide a lawn mower havinga light frame which still provides a very rigid construction wheretwisting of the frame does not occur and wherein the cutter bar remainsyvery rigid. In addition such lightweight but very rigid frame should besimple to fabricate with the accuracy required so that the manufacturingcost is low.

It would also be desirable to provide an improved reel type lawn mowerpropelled by an electric motor in which means are provided to insureproper shearing action between the cutter bar and the reel at all times.Thus there would be available a lightweight reel type lawn mower whichcan be startedv and stopped merely by they ickof a switch. In any lawnmower it is essential to be able to a, y1V renali adjust the height Yofthe cut. Hence, at certain times of the year it is desirable lto cutthegrass much shorter than at other times. Consequently; itis desirableing-a reel type lawn mower to Vprovide simple and foolproof means .foradjustingV the height of the cut, and simple and foolproof means foradjusting the shearing action'between the'cut-V It is another object ofthe present invention to provide a reel type lawn mower having anintegral frame of lightweight metal which provides a very rigid andsubstantially twistproof construction. e e e It is another object of thepresent invention to provide a reelt e lawn mower in which im rovedmeans are ro- '7' yp p p of the controls of the wheel drive mechanism`of the vided for adjusting the reel relative to a cutter bar fixed tothe frame.

Still another object of the. present invention comprises the provisionof an improved reel type lawn mower powered by an electric motor withimproved means for. adjusting Ithe power drive between the motor and thereel ofy the lawnr mower.

Yet another object of the present invention isrthe proof FIG. 8,assuming that FIG. 8 showsthe complete structure; l

' FIG. 10 is a'fragmentary sectional View taken on line 1% 10 of FIG. 8,alsol assuming vvthat FIG. 8 shows the complete structure; i

' FIG.-11 is a sectional view taken onv line 11 11 of FIG. 3 assumingthat FIG. 3 showsv the'complete structure; j l

Y FIG.- 12 isa greatly enlarged fragmentary front elevational View` ofone end of the lawn mower of FIG. 1 withjcertain portions broken away orshown in section;

Y FIG. 13 isan exploded perspective View of a portion e, of thek motorframe and drive mechanism;

n n of'FIG. 3;

FIG. 15A isa fragmentary sectional view' taken on line FIG. 14 isV anenlarged sectional view taken on line FIG. 16 is'a sectional view takenon line 16 16 of FIG. 12, assuming FIG. 12 shows the complete structure;

V20km una 17,-17 of FIG. 2;

vision of an improved reel type Vlawn mower with means for maintainingtheY entirelength of the cutter bar in good shearing engagement with thereel.

A furtherrobject of the presentinvention resides inY new vand improvedmethods of manufacturing a lightweight yet Vrigid frame for a reeltypelawn mower.

Still another object of the present invention resides in improved meansfor supplying power to the ground supporting wheels whereby the lawnmower isI driven over the area to be mowe Y i 'n Further objects andadvantages of the present invention will become apparent as thefollowing description proceeds, and the features of novelty whichcharacterize the invention will be pointed out with particularityin theclaims annexed to andforming a part of this specification. For a betterunderstanding of the present invention, reference may be had to theaccompanying drawings in which: 1' g FIG. 1 is a perspective view of apoweroperated lawn mower built inaccordance with the present invention;e

FIG.V 2 is an enlarged front elevational view of the lawn mower of FIG.1 with the handle portion removed and'withr certain portions cut awayorshown in section lto illustratedetails of the present invention; j

FIG. ,3- is a sectional view taken on line 3 3 of FIG.

with certain portions cut awayY and with thev controls in the driveposition, Vassuming that FIG. 2'shows the complete structure; ,Y f A n vVFIG-4 isa sectional view taken on line 4 4 of FIG. 2, again assumingthat FIG; 2 shows the complete structure and with the controlsin thesame-positionas FIG. S;

FIG; 5 is a sectional View withY certain portions ,cutaway taken online"5 5 ofV FIG. 4, assumingthat 4 fshows the complete structure; .f

FIG. 6 is a sectional View taken on line 6 6 of FIG. 2,V

also assumingV that FIG. 2 showsfthefcomplete structure;

FIG..1.7 is an enlarged fragmentary sectional View taken presentinvention different l from that shown Yin FIGS.

. 3 and 4 of the drawings;

FIG.`2O is 'a fragmentary sectional view illustrating aparticular'position of the handle mechanism of the present inventionstill different from those shown in FIGS.

' 3,118 and 19 of thedrawings taken on line 2(1 20 of FIG. 2;" Y

e FIG. {21,is av greatly enlarged sectional view with cer- A`. tainportions cut away taken on line 21 21 'of FIG. 6; and

FIG.V 22 ispan enlarged view of one end of the motor housing partly insection showing the air cooling inlet, etc.v V- A j Brieflj/,the presentinvention is concerned with a lightweight electric powered reel typelawn mower vhaving la lightweightframe of cast aluminum with va tubularsteel insert to give` it strength and` rigidity without vincreasing *theweight. Thecutter Vbar isiiXedk to the frame, and

' .means are provided to bow thercentral part of the cutter bar toinsure good cutting action at the center thereof. The vreel iseccentrically mounted sothat it may Vbe adjusted relative tothe cutterbar. yAn electric motor and gear reduction mechanism is providedr topower both therreel and, if desired, the ground wheels which support themowereand associated carriage.V rImproved handle operated means forapplying driving torque to the ground wheels at theselection of theoperator is provided. Simple Y the height'and adjusting the shearingaction are provided. l y Referring now to the drawings, therev isillustrated .a

kreel type power drivenrlawn mower generally indicated at 3) comprisinga rigid frameembodying the present invention designated as .31, withinwhich frame is ro- FIG.y 7 is a'fragmentary sectionalview taken on lineV7 7 of FIG. 2, also assuming thatFIG. 2 showslthe complete structure;

FIG. 8Y is a greatly enlarged fragmentary View, partly lin j section, ofthe reeladjusting portion of FIG; 3 withra cover portion shown in openkposition;

tatably journaled'a reel 32 having a reel shaft 32a. The framev 31atfectively defines `a sort of carriage supported lbylrubher Ytiredground wheels generally designated at 'v 33 andf34, VSuitablyV mountedon ythe carriage or frame isha primeV mover .generally'dsignated at 35,which is a combined electric motor and reduction gear mechanism. Forthepurpose of guiding Vthe carriage, there is included 'a vhandle assemblygenerally designated at 36,l which handle assembly is pivotallyassociated withthe carriage or frainel in a manner described in detailhereinafter.

" Y The handle assembly best shown in FIG.v 1 of the drawings isillustrated as being very similar to that disclosed vin Jepson PatentNo..-2',V926,478-referred to above. As

illustrated, the handle assembly 36 comprises a lower tubularVU-shapedmember V37 having the bight portion there- Cif-,secured to an upperhandleassembly 38 V'comprising tubular members 38a and 3817." TheU-shaped member 37 defines a fork with the Vends thereof flattened asindicated at 37a and 37b for connection with the mower framed-1 asdescribed hereinafter. These tubular members 33a and 38b have the upperends thereof welded or otherwise secured together and then this assemblyis Apreferably bolted as by fastening means 40 to the bight mountedwithin the space defined by the divergence of the lateral projections ofthe tubular handle portions 38a and 68h. The power cord 4S preferablyterminates in this space so as to permit ready connection to be made tothe switch 48. Moreover, a power cord 49 enters this area through theupper end of the tubular handle member 38D and through an opening in thegrip 44 associated with that member 3Sb. Suitable strain relief means,not shown, are provided for the cord 49, and to support the cord at agreater distance from the handle assembly and also to prevent oreliminate wear where it enters the grip 44 a coiled spring 50 isprovided, arranged concentrically with the power cord and the end of thehandle grip portion 44. The power cord 49 is very short and terminatesin a conventional male type plug connector 51 for connection with aconventional extension cord. In this way the power cord may bedisconnected closely adjacent the mower and a minimum of extension cordneed be normally associated with the mower 30. A suitable guard 53 isprovided around the handle or lever of the switch 48 to preventinadvertent actuation thereof and to protect the same.

It will be understood that to mow a substantial area quite a length ofextension cord may be required and a storage problem with respect tosuch cord is involved. It has been found desirable to store the cord onthe mower,

f and to this end the handle assembly 36 is provided with a cord bracket55, which is held in place by the same fastening means 40 which hold theupper and lower handle portions together. The cord can then be wrappedaround one of the handle grip portions, such as 44, and the cord bracket55.

An important feature of the present invention resides in theconstruction of the frame, which is of lightweight and yet very rigidconstruction and results in a lightweight and yet satisfactory poweroperated reel type lawn mower. Referring particularly to FIGS. 2, 3, 5,6, ll, 13 and 2l of the drawings, the frame 3l is essentially a castingof aluminum or other lightweight metal, and is an 'integral unit. Asillustrated, it comprises end plates 31a and 31h which are held inspaced parallel relationship by a pair of crossbars 31C and 31d,respectively. In order to reduce the weight, the crossbar 31C, inaccordance with the present invention, is not a solid casting, but isactually a hollow cross rod of cast aluminum or the like surrounding anembedded steel tube 57. (See FIGS. 6,

- 11, 17 and 21.) The cross rod 31d on the other hand is merely a hollowsteel tube having its ends embedded yin the cast end plates 31a and 31h(see FIG. 12). The

ends of tube 57 are likewise embedded in the end plates 31a and 3111thereby to provide an integral frame of lightweight and yet having greatstrength against twisting forces or the like.

Since crossbar 31d is essentially only a steel tube it will bedesignated either as steel tube 31d or crossbar 31d. Preferably thesteel tubes 31d and 57 are each formed of cold rolled steel and aresuitably anchored during the casting operation of the lightweight frame31 in the end portions 31a and 31h by providing the exterior endportions with a roughened or knurled surface designated at 59, bestshown in FIG. 2l of the drawings. Any other means for securely unitingthe ends of the steel tubes with the cast end plates 31a and 31h could,of course, be employed. The use of these tubes in addition to providingrigidity and reducing the weight provides a means for insuring goodcutting action at the center of the cutter bar to be described in detailhereinafter. Thus, without the use of any cores during the castingoperation, hollow tubes are provided extending from one end of the frameto the other.

In accordance with the present invention a die casting operation isemployed in making the frame 31 having the anchored steel tubes 31d and57 either wholly or partially defining the crossbars 31d and 31Crespectively. Since the frame except for the steel tubes 31d and 57 ismade of aluminum there is the problem of differential expansion duringthe manufacturing process. Preferably the molten aluminum during the diecasting operation has an initial temperature of about 1300"V F. Thealuminum heats the ends of tubes 31d and 57 to about 1000 F. before thecomposite structure begins to cool. Actually, the portion of the tube 57between the ends thereof which is embedded in a relatively thin aluminumtube defining crossbar 31C is heated to a less extent during the diecasting operation than the end poritons of the steel tubes which areembedded in a relatively large mass of aluminum. Consequently, as theframe cools after the die casting operation, the aluminum portion of thecrossbar 31C will tend to shrink much more than the steel tube 57. Toprevent such differential shrinkage, the steel tube 57 and likewise thesteel tube 31d are heated to a temperature of about 1000 F. at the timethey are inserted into the die casting apparatus, and the die castingoperation is begun immediately thereafter.

Before considering the details of the die casting operation attention isdirected to the fact that the crossbar 31C in accordance with thepresent invention essentially denes a cutter bar support. Thus, as bestshown in FIGS. 6, 1l, and 17 the crossbar 31C includes a rearwardlydirected web portion 31e including a plurality of spaced paralleldepending reinforcing webs or ribs 31f (FIGS. 6, 12 and 17). The ribs31] have the forward portions thereof cut away slightly to define aplurality of spaced supports having the lower edges disposed in a commonplane so as to define a rigid support for a cutter bar 60 which issuitably clamped against the bottom of the ribs or webs as by suitablescrews 61 the heads of which are disposed in pockets 62 spaced along thelength of the web 31e as best shown in FIGS. 2, 5, l1 and 17 of thedrawings. The cutter bar 60 is, o'f course, formed of good cutting steeland is provided at the end thereof remote from the crossbar 31C with anupturned portion 60d which denes the cutting surface for providingshearing action with the reel 32 in a manner well understood by thoseskilled in the art. The cutter bar 6i) is preferably provided withtapped openings for receiving the screws 61 for clamping the sameagainst the edges of the ribs 31j in a manner best shown in FIGS. 6 and17 of the drawings.

The end plates 31a and 31h of the frame must be parallel with oneanother in the completed frame. To this end it is important during thecasting operation to make sure that any differential expansion betweenthe steel tube 57 and the adjacent aluminum port-ions of the crossbar31C and the associated portions 31e and 31f do not interfere with thisparallel relationship. In order to insure that d-uring the castingoperation the tube 57 contracts or shrinks the same amount as thealuminum portion of the crossbar 31C and the associated cutter barsupports and to eliminate differential movement of the cutter barsupport 31e and the associated integral aluminum portion of crossbar 31Crelative to the steel tube 57, a steel die is used in the die castingoperation and this die is provided with core portions complementary tothe pockets or recesses 62 as well as core portions which fit betweenand define the spaced ribs Slf. These ribs Blf are essentiallyreinforcing Y "a1-renee f 27 ribs or webs spaced uniformly along ythecrossbar 311e and they serve as keys Yrelative, tothe core portions ofthe die spaced therebetween. Since the die is made of steel like thesteel'insert 57 it does not shrink as much as the aluminum which definesthe crossbar 31C and the associated cutter bar support during cooling ofthe Vcast aluminum, and the webs are ribs 31j" between the core portionsofthe die as well as the coreportions of the die fittingV intothepockets 62 fact. to keyV the aluminum crossbarSlc and its integralcutter bar extension to the die. Thishas theefect of stretching thealuminum defining the crossoar 3io uniformly along its length as` itsolidilies and cools during the casting operation thus keeping thealuminum portion of the crossbar from shrinking more than the steeltube'.

It will be apparent that by preheating the steel Vtube k57 Y and 3M' andalso by the keying operation of the die relative to the castingv thatthe end platesla and Sbmare l Y maintained parallel to each other.

Yvide the4 necessary clamping" force to` support' the prime mover 35from frame 31.'

i To complete the housing" for theruuit 35, there is provided amotorhousing section 7'7 of cup-shaped configura- :housing 70 with aninterposed gear'hou'sing closure plate aud'bearing. support member'79'clamped therebetween. Electric motor 71 is drivingly connected to asuitable fan n 8@ for circulating cooling air through the end'of thelmotor housing 77 remote'from the gear housingltl Vand out through anexhaust opening 81- (FG. 2) defined In order that the frame 3i andparticularly end plates 31a and Sib may suitably support the cuttingmechanismV` the die for the die casting operationis provided withsuitable end cores to define certain openings and thelike Y,in

Yframe 31 for supporting the reel'and other portions of the mechanism.Also for purposes which will become apparent from the ensuingdescription the ends of the hollow crossbars 31C and 31d are open andaccessible vfrom the at thebottompf the plate 79. The combined overloadclutch andl reduction and. gear mechanism `72 forms no part of thepresent invention, ,butprovides an arrangement for driving the reel 32at the proper speed and also a safetyV device whereby, if the lreel 32should be 'stopped as by wedging a foreign object between the bladesofthe reel 32 and the cutter bar d0, the power. transmission between theelectric motor 7l and the reel 32 will be interrupted. As far as thepresent invention is concerned, the reduction gear mechanism-andcombined overload clutch unit '72 includesan output gear 83 which ismounted on an output drive shaft 8d' suitably journaled withintheftapered A portion of the'V gear housing 7i?. The end of the outputouter ends Vof end plates Sllaand Elib of the frame 3l. Y

. Thus, as best yillustrated in FIGSJI l', 17 andk Zl'rof the drawingsthecrossbar'31c provides an elongated passageway 6d from end toVendthereof which is accessible'from the ends of the frame. Similarly thecrossbar 31d as -best shown in FlGS. lZand v13 Vof the Ydrawings definesthe passageway 65 ltherein which'is alsoaccessible from either. end ofthe frame 3l.

For the purpose ofV enclosingY the upper parte` of the` shaftd extendingoutside the housing 76 is disposed adjacent the end plate'lb Yof theframeV 31 and hassecured Vthereto a suitabley sprocket'itFlG. 7)forltransmitting power to, the.` cutting reel 32 and when desired to thej groundrw'heels 33 and 34; 'For the purpose of rotatablysupporting thereel 32 and kspecifically the reel shaft 32a in frame 3l, the end platesSla and 31h are each provided with enlarged aligned opencuttingmechanism, the frame 31 preferably supports a# platform 67 which isypreferably formedof sheet metal'y and provides a sort of 'deckVconstruction or top guard ings or sockets designated as 86 (see FIGS. 5,10 and 13 ofthe drawings) defined by an annular flange 86a formedAintegrally with the frame 31. The cast'. metal defining the @end plates3M and 3l!) is vso arranged rwithin these openover the reel 32. AsVillustrated in the `drawings,,the'deck f is provided with a dependingperipheraly flangek and Vat either side of the mower suitabledeckusupporting plates 68a and 68b are provided which arepreferaolywelded or otherwise` secured to the deck or platform 67. These plates68a and'b, which except that one is a right hand plate and the othery isa left hand plateare identical, arev bolted as by fastening means 6 9 totheframe 3l.

Mounted' above the platform or deck 67 is the power unit 35 which issuitably supported from the frame 31. The power/or electric motor unit35 is preferably identical with that disclosed in the copending Lillapplication, Serial No. 772,881, filed November 10, 1958, now Patent No.V3,035,675, and assigned to the same assignee as the presings .orsocketV Se as to defin'e'an'annular shoulder generally at right anglesYto the annular flange 36a and having a -fsomewhatiangularly disposedwall defining shoulder v87.

-Y The sockets S6 are adapted to receive reel bearing supports 89 and 9d(FIGS. 5, 8, 9 and l0) for supporting the reel bearings describedhereinafter. To increase the'rigid- `ity of the end plates 31a andlb andto provide maximum Support for the sockets 86, the casting defining theframe 3l preferably includes reinforcing'struts V88 best shown in'.FIGS. 3 and 13'of the vdrawings whichrhave the same ent application.As best shown -iu FIG. 2 of the drawings, v

the power unit 35 is essentially a combined electric motor, reductiongear, and overload clutch mechanismY fully dis'- closed and claimed inthe concurrently filed copending application referred to above. Asillustrated in FG. 2,V there is provided an electric motor 71 and acombined reduction gear mechanism and overload clutch mechanism 7?.mounted within a suitable housing. As illustrated, this housingcomprises several sections and includesY a gear housing 70 preferablyformed as a Vgenerally cylindricalY casting including an elongatedtapered lportion and also inv cluding integrally formed armsv orbrackets 7ilaand flb f which are suitably clamped to the crossbar 3E@ ofthe-v frame 31 as described hereinafter, as by suitable clamps '73. Thegear housingffl thus forms a support for the en-Y tire power unit 35. Asbest shown in FIG. 6 of the draw# ings, the arms such as 70a Vand 7Gbeach terminate in a downwardly directedrecess 74a which, wtih upwardlydirected Vrecess 7411 in each of clamps'73, receive the crossbar 31d inclamping relationship therebetween. The clamps 73 each have a hookportion '73a at oneend toengageea cooperating extension` on theassociated brackets 79a or 7Gb, and clamping boltsda'and nuts'75b pro-.K

depth as flange 86a and radiate therefrom. The shoulder 87 effectivelydefines'a frusto conical seat best shown in FIG. loof the drawings forthe reel bearing supports 89 andk 90. Y v f n Y The cutter bary o@ asdescribed above is rigidly secured to the frame 31 and hence relativeadjustment between the reel532 kand the cutter barV 65D can only beaccomplished by adjustment of'theireel position. To thisend the 'reelbearing supports -39 and 90 as bestV shown in 'FlG 5 and l0 of thedrawings are provided with eccentric openings 91 and 92 thereinrespectively. These openingsl andrrZare so arranged as to respectivelyreceive therein combined radial and thrust bearings 93 and 94,

which Vbearings are preferably press fitted into the eccentric openings9E and 92.y A suitable Cwasher95 (FIG. 10) lnsertable into ag-roove'defined inthe bearings such as'93 and 94 limits the extent towhich the bearings are pressed into the eccentric openings-91 and92`respectively.

Iny 'view ofV the eccentric Vopenin`gs'9l. and 92, it will beYunderstood that rotation of the reel bearing supports 89 kand Ml withinthe sockets Se will cause relative movement of 'theA reel shaft 32asupported thereby toward or'away from the cuttery bar 60. v A' f Inorder to adjust the positions of the reel bearing supports S9 and 9i)inthe sockets S6 thereby to adjust the reel 32 relative to thecutter bar6i? the flange 86a is discontinuous for a short section, effectively todefine an arregle/a 9 access opening 96 best shown in FIGS. 8 and 13 ofthe drawings which opening is defined by shoulders 98 and 99 at the endsof flange 85a determining the discontinuous portion thereof. Thisopening permits the ready entry of a suitable prying tool such as ascrewdriver or the like. So that such a prying tool may move reelbearing supports 89 and 90, the peripheries of the major portion of thereel bearing supports 89 and 98 are provided with gear teeth 89a and 98arespectively. A prying tool inserted through the openings 96 can thenreadily engage the teeth such as 89a or 98a. By using the shoulders 98or 99 as fulcrums for the prying tool, rotation of the reel bearingsupports 89 and 91) with the resultant movement of the reel shaft 32atoward or away from the cutter bar di) can readily be accomplished. Inadjusting the relative position of the reel and cutter bar therelatively equal adjustment of the two reel bearing supports 89 and 99will of course be accomplished to insure proper cutting action. So onemay readily see that these reel bearing supports 89 and 98 are in aboutthe same relative positions they are preferably each provided with anannular flange 89h and 9Gb respectively which flange overlies theannular flanges 86a defining the socket 86. The flanges 8911 and 90bpreferably each include a notch 116 (FIGS. 3, 8 and 10) thus permittingthe operator to see readily that the notches 116 in the reel bearingsupports 89 and f 90 are roughly in the same relative positions.

Once adjustment of the reel 32 relative to the cutter bar 60 has beenaccomplished it is desirable to lock the adjustment so that it cannot beinadvertently changed. To this end there is Iprovided a reel bearingsupport lock plate 191 best shown in FIGS. 8 and 9 of the drawings whichis provided with a channel 182 having tapered side walls for receivingthe gear teeth 89a or 98a as the case may be therein, To provide goodclamping action a flat leaf spring 103 is preferably disposed within therecess 102 so that it may be tightly clamped against the gear teeth suchas 89a or 99a thus firmly securing the reel bearing supports 89 and 90in fixed adjusted position within the sockets 86. To apply clampingforce to the lock plates 101 the frame at each of the end plates 31a and31h is provided with a boss portion 104 having an opening 10S forreceiving a clamping screw 1136. The clamping screw preferably engages asquare nut 107 disposed in a square recess 188. The end of clampingscrew 196 preferably is received within a shallow recess 189 in the lockplate 181. It will be appa-rent that upon adjusting the screw 106 thenut 187 will be forced against a shoulder 118 defining the upperboundary of the recess 188 and the clamping force will be transmitted tothe lock plate 191 and through the leaf spring 183. To provide goodclamping action the lock plate 181 is of arcuate configuration so as toconform to the periphery of the gear teeth such as 89aor 96a. Thus, asthe lock plate 1111 is forced down against these teeth which also havetapered side walls, they are wedged tightly between the correspondinglytapered side Walls defining the recess 182. The function of the leafspring 183 is to take up any backlash and keep the reel bearing supports89 and 90 seated against the lower portion of the sockets 86. Thus, asthe clamping screw 106 is released the spring 183 which is a straight,flat piece of leaf spring tends to straighten `out and keeps a limitedamount of pressure on the reel ybearing supports 89 and 90.

In order to keep dirt from entering the opening 96 a suitable cover 112is provided which cover is pivoted as indicated at 113 to the associatedend plate 31a or 31b. The cover 112 is provided with a spring latchingclip 114.l which is engageable with a suitable lug 115 formed as anintegral part of the end plate such as 31a and 31h. The cover 112 isshown in the open position in FIG. 8 of the drawings and in the closedposition in FIG. 3 of the drawings. When adjustment of the reel 32relative to the cutter bar 61D is desired the covers 112 are opened topermit access with a suitable prying tool as fully described above.

For the purpose of driving the reel 32 from the output shaft 84 andconsequently the sprocket 85 of the power unit 35 there is secu-red tothe reel shaft 32a a suitable sprocket 118 (FIGS. 5 and 7 of thedrawings). A suitable chain 119 then interconnects the sprockets 85 and118 in a manner well understood by those skilled in the art. Since thesprocket is mounted above the platform or deck 67 and the sprocket 118is mounted below this platform 67, a suitable opening 120 is defined inthe platform for the chain 119. So that the operator is protected fromcoming in Contact with the sprocket -85 and the chain 119 above theopening 120 there is provided a suitable top chain guard 122 which as isbest shown in FIGS. 2 and 7 is secured to the platform or deck 67 byfastening means 123. This top chain guard 122 may be a casting or asheet of metal stamping as the case may be. In order to enclose thechain 119 and the sprocket 118 below the platform 67 there are provideda pair of cooperating chain guards and grass shields 124 and 125 (FIGS.6 and 7) suitably secured to the inside of end plate 31!) of frame 31 as4by fastening means 126 (FIGS. 3, 4, 5 and 12 of the drawings). In orderthat the reel 32 may be adjusted relative to the cutter bar 60 theguards 124 and 125 are provided with means defining an elongated opening127 (FIG. 7). Preferably a suitable arcuate grass guard 129 is securedto the front chain guard section 125 and partially surrounds the reelshaft 32a as best shown in FIGS. 5, 6 and l2 of the drawings. To furtherprevent the entrance of grass into the opening 127 there is provided agrass shield 130 which is an annular cup-shaped member secured to theshaft 32a as clearly shown in FIGS. 5, 6 and l2 of the drawings. Asimilar but somewhat smaller grass shield 128 is provided at the otherend of the reel shaft 32a as clearly shown in FIG. 5 of the drawingswhich is secured to the shaft and is concentrically disposed withrespect to the reel bearing support 89.

From the above description it will be apparent that upon energization ofthe electric motor 71 a driving torque is supplied to the reel 32a, andby virtue of the reduction gear mechanism the desired speed of rotationis obtained. Moreover, this reel may be adjusted relative to the cutterbar 68 to insure proper cutting action. In order that the ground wheels33 and 34 may also be driven from the electric motor 71, the shaft 32ais provided at one end with an integral extension 32h which extendsbeyond the end plate 31b and has suitably secured thereto as by a key131 (FIGS. 4 and 10) a friction drivel roller 132. Except for anassembly problem, the other end of reel shaft 32 might be provided witha similar extension such as 32b. However, in order to permit readyassembly of the lawn mower parts there prefenably is provided a separatestub shaft 133 (FIG. 5) which is threadedly secured to the end of thereel shaft 32a adjacent the end plate 31a 'of the frame 31. Secured tothis stub shaft 133 is a drive roller 132 identical in every respect tothe drive roller associated with the shaft end 32h. The details ofconstruction of these drive rollers is best shown in FIGS. 4 and 10 ofthe drawings. In assembling the reel 32 to frame 31 the shaft 32a hasthe end B2b thereof first assembled with end plate 3111 and associatedreel bearing support 98. A suitable distorted spring C-washer 135 isthen applied to a grove 136 in the shaft 32a. This resilient `C-Washerthen becomes an end thrust washer bearing against the bearing 94 toprevent movement to the right as viewed in FIG. 5 of the drawings. Anend thrust washer 137 is then forced against the bearing 93 when thestub shaft 133 is secured to the end of the shaft 32a thus preventingmovement to the left of the reel shaft 32a as viewed in FIG. 5 of thedrawings. Additionally the shaft 32a is provided with shoulders such as140 shown in FIG. 10 of the drawings, which provide a thrust bearing forbearing against the other sides of the bearings 93 and 94.

As was pointed out above the center portion of the cut- Y ter bar 60 isbound to receive more wear'than the end portions. To insure propershearing action' of the reel 32 the form rof an elongated sleeve.Suitably secured tothe peripheryof the disk wheel portion 159 is adriving rim along the entire length of the cutter bar 69 means are Y Y nY rubber. tirel which insulatesrthe wheels from ground provided inaccordance with the present invention to bow the centerrportion` of ,thecutter bar toward theV reel v32 if necessary. To this end'there isprovided as best shown Y. in FIGS. 11, 13 and 21 a tension bolt 142extending within the passageway 64 defined within the hollow crossbar31o. Suitable tension bolt Awashers 143 are providedy for either end ofthe tension bolt 142. These washers 'are circular but are provided withan integral projection 143:1

receivable @in a cooperating notch 144l (FIG. 13) defined in the endplates 31a and'31b immediately vadjacent the opening leading into thepassageway 64. Each. of4 the washers is provided with a square opening145 which opening is eccentricallygpositioned relative to the washer143.v vThe tension -bolt 142 has a square shoulder 142a to engage thesquare opening 145 in the associated washer 143. The other end of thetension bolt 142 is threaded as indicated at 142b to receive aclamping'nutle. To per form the bowing action there isv securedto thecenter portion of the tension bolt 142 an angle memberlft 151whichalso'supports the rubber tire 16).A It is this which necessitates'theV grounding Vconductor 158 referred toV above. T he driving rim 161is disposed in concentric relationship with the sleeve and, is providedwith an annular drivingrecess or channel 163 Ywhich vpreferably i has'la driving surface complementary to the shape of the truncated pyramid.

driyerollers 132. As best shown in FIGS., l0 and l2 of the drawings thedriving channelj163 for the wheel 34 has sidewalls ilaringoutwardlyytowards the mouth of the 'channel to dene a cross section in the formof a Correspondingly the drive rollers 132 vwhich are formed of asuitable friction material "such as a fiber or the like are providedwith tapered side walls 1324 to make friction driving engagement with'die (FIGS. l1 and. 17) which may be made from flat Vwirev or the'likeand which is suitably welded or otherwisesecuredl to the tension bolt142. Since the openings 145 areY disposed adjacent the top ofthepassageway 64 as viewed in Y,

FIG. 11 of the drawings, by virtue of the particular orientation'ofthewasher 143 occasioned by the lugs 143:1 and notches 144, when tensionis applied to the tension ybolt 142 by virtue of the nut 146 there willbe' produced an upwardly directed force applied to the center of thecrossbar 31C by the angle member 14S." Consef' quently the cross bar31C, the cutter `bar support. 31e.

and `cutter bar 60 may be bowed toward the reel at the center thereof toinsure proper shearing action under all conditions. y Y

Iny order to support the frame 31 andl consequently the lawn mower fromthe Aground' wheels 33 and 34 there are provided a pair of Wheelmounting plates 149 and V151i associated with the frame end plates 31aand 31b respectively. Each of these wheel mounting plates 149 and 151iis pivotally mounted to the frame 31. To this end these plates are eachprovided with a pivot shaft 151 suitably secured thereto which pivotshafts are adapted to extend into the endsV of the passageway 65`defined in Y'the cross-v bar 31d. As best shown in FIGS. 12, 13 and 16of the drawings a suitable bearing sleeve 152 preferably formed of alubricant impregnated kmaterial is driven into-earch end of thepassageway 65 in crossbar 31dl and thep-ivot shafts 151 are insertedtherein. A In order to hold theV wheel mounting plates V1.49 and 151i inassembled relationship with the frame the Ypivot shafts Vare preferablyprovided with an annullar'recess 153 for receivingal suitable key or pin155, inserted through Yaligned openings 156 Vin they cnossbar 31d andthe sleeve 152 as best shownV In this 'way the Y wheels into and out ofdrivingengager'nent with the VdriveY rollers 132. Y

The wheels 33 and 34 are essentially identical except that the wheel 34is provided with a peripherally'disposed grounding conductorV 153 (FIGS.2 and 12) which' isf65 suitably electrically connected to the metalwheel portions As will become apparent from Vthe walls'of the drivingchannel163 Yof tlre'wheelA 34. With this arrangement it willbe apparentthat as the wheels and speciiically the drive channels 163 thereof areforced into engagement with the Ydrive rollers 132 the greater forcebiasing the rollers'into the channels'the more firm the drivingengagement by virtue of the flaring walls of the recess 163 land thetaperedv walls 132a of the friction drive rollersV 132. YAs best shownin FIG. l2 of the drawingathe wheels 33 and 34 are suitably mounted onwheel axles 164 threadedly engaging suitable one of a plurality ofopenings designated as 165 in the wheel mounting plates 119 Yor 151i asthe case may be. A suitable sleeve bearing defined by concentric sleeves167 and 1&8 is provided for the wheels V33 and 34.

' It is common practice to provide'means for adjusting .height ofthe cutin lawn mowers andto thisend instead of a single opening 165 in thewheel mounting plates 149 and 151i a plurality ofl openings spaced in apredetermined-manner are rprovidedv .as best vshown in FIG. 13 of thedrawings. As illustrated tive tapped openings 165 4are providedVdesignated as 165a, 16511, 165e, 165d and 165e, but only three ofVtheseV namely 165er, 165b and 165C are used for, height of cutadjustment. When the wheel axle 164 threadedly engages the opening 165athe maximumheight of cut is obtained. A lower cut is obtained whenarde164 is in opening 165b as is the case in FIGS. 3 and 12 of the drawings,anda still lower cut is obtained when axle `164 is threaded in opening165e. By virtue of the elongated sleeve Y159e: and the drivingrim 161disposed in concentric relationship, the disk portion 159 may besufficiently removed from the associated wheel mounting` plate such'as149 andr150 so that the friction drive roller 132 may readilyengage withthev driving recess Y153 as clearly showninFIG. 12 of the drawings.

Y For the purpose of biasing the friction drive'rollers 132 I intodriving engagement with thefwheels 33 and 34and specifically `with the`driving recesses 163 -there is provided for each wheel .mounting'plate149 and 150 va l tension Vspring 171i having one end thereof engaging arecess v171 provided in an 'ent'e'nseionv 172 of the wheel mountingplates 149 and150. The other end ofthe ten- Y sion spring .170 isconnected' to a pin 173 VVsecured to the frame 31 as by vbeing fastenedtoa suitable opening such as 174'defined in the endV plates 31ay and31b.'Ihese tension springstend to bias the ywheel mounting plates in adirection to cause the wheels to -move into driving Y engagement withthe drive rollers 132. For example,

preferably in exactly the same manner as the arrangement Y K disclosedin Jepson Patent No.' 2,926,478 referred to presence .or 'absenceofgrounding conductor 153v are Y identical, the wheel 34 Vonly will beydescribed in defait. Asiuusirad in FIG. 12 or ai@ drawings the whenv 34comprises a metal disk 159 essentially deiining a diskY wheel with anintegral central bearing support 159e in as viewed in FIG. 3 of thedrawings the springs 170 jbias Ythe' Wheelrmounting platesV 149 and 15.0yin a clockwise direction about the pivot shafts 151 which means thatthe wheels 33 and 3,4 to the left as viewed in FIG; 4andvcon-` sequentlyinto illustrated. l y, y n f From .an examination of FIGS. 3 and 4 ofthe drawdrivingY engagement with theroller 132 as ings it willbe notedthat the wheels 33 vand 34 tend to support the front partl of the frame31. In order to sun port the rear Y'of the framel 31 there is provided aground roller 177 'which may actually comprise a'plurality of sectionsas indicated in FIG. 2 of the drawings desigf nated as 177a, 177!) and177e. These rollers are suitably f in suitable bearings 179 and 180riveted or otherwise secured to roller brackets 181 and 182respectively. Freterably the brackets 181 and 182 are secured to theframe 31 and particularly to the end plates 31a and 31h thereofrespectively by suitable bolts 134. As illustrated these bolts extendthrough an elongated arcuate opening 185 (FIGS. 3 and 4) in each of thebrackets 181 and `182. This elongated opening permits different relativepositions of the brackets 1811 and 182 relative to the frame 31 andconsequently also enters into the picture with respect to 4adjusting theheight of the cut of the mower 30. As illustrated the frame 31 isprovided on each of the end plates 31a and Sib with suitable indiciadesignated as 187 which indicia cooperates with .an index or pointer 18Sdefined on each of the brackets 181 and 18,2. This indica has aplurality ot consecutive numbers from one up to tive or six indicating aplurality of adjustments. Thus by utilizing the openings 165er, 16511and 165C in Wheel mounting plates 149 and 150 and the various settingsof brackets 181 and 132 there are provided ready means of adjusting thecut not only by the position of the brackets 131 and 182 but also theposition of the axles 164 of the ground wheels 33 and 34.

For the purpose of securing the handle assembly 36 to the motor frame 31there are provided a pair of handle mounting plates 190 and 1911pivotally secured to the end plates 31a and 31b respectively. As bestshown in FIG. 14 of the drawings suitable handle mounting plate pivotbolts 193 extend through suitable openings 194 `one provided in each ofthe end plates 31a and 31b. Preferably the end plates 31a and 31]; areprovided with a recess concentric with the opening 194 to receive abearing washer i195 against which the handle mounting plate bears. Asuitable shouldered nut 196 secures the handle mounting plates to thebolts 193 in a manner to permit free pivotal movement thereof about theaxis of the bolts `193.

In order to secure the handle assembly 36 and more particularly theportion 37 to the handle mounting plates 190 and 191 each of the plates190 and `191 is provided with an elongated arcuate opening 197 and aseco-nd opening 198 (FIG. 13). A suitable pin 199 extending through theopening 198 is preferably welded to the associated mounting plate suchIas 190 and 191 and is adapted to engage a cooperating opening 200defined in the associated flattened portion 37a or 37b of the U-shapedhandle member 37. The handle member 37 is also provided with openings201 to receive a suitable bolt 202 and an associated nut 203 whereby thehandle 36 may be secured to the plates 190 and 191 and hence to themower 30. It will be understood that the arcuate slots 197 provided inthe handle mounting plates 190 and 191 permit adjust ment of theposition of the handle assembly 36 relative to the handle mountingplates 190 and 191 so that the handle may be adjusted for a tall or ashort operator as the case may be.

Some means must be provided to control the driving condition of the lawnmower 30. In other words it must be possible to have the driving rollers132 in a no drive condition and selectively control the same so thatthey may 'be moved to a drive condition in driving engagement with.drive channels 163 to propel the mower over the area to be mowed. Inaccordance with the present invention the control of the mower from thedrive to no drive position is accomplished by limited pivotal movementof the handle assembly 36 and to this end each of the handle mountingplates 190 and v191 is provided wit-h a recess or notch 205 for securingthereto a suitable cam roller 206. As best shown in FIGS. 13 and l5 ofthe drawings, the cam roller 206 is mounted on suitable ball bearings207 and supported on a bolt 208 which is clamped `within the notch 205as by a nut 209. Preferably the surface adjacent the notches 205 on eachof the handle 1d mounting plates 19t) and 191 is roughened as indicatedby 210 in FIG. 15 to insure that the cam roller 206 is securely fastenedin associated handle mounting plate.

It will be appreciated that to control the drive and no drive conditionof the lawn mower 30 it is necessary pivotally to move the wheelmounting plates 149 and 150, and to this end each of the wheel mountingplates is provided with an elongated somewhat arcuate lobed opening 211,`the coniiguration of Vwhich is clearly indicated in FIGS. 3, 13, 18, 19and 20 of the drawings. This opening 211 has a plurality of lobes alongthe top edge thereof designated as 2111s, 2Mb, 211e and 21M'. The camroller `20:? is disposed in this opening whereby pivotal .movement ofthe handle `36 causes rollers 206 to assume different positions in theopenings 2111 of the wheel mounting plates 149 and 130. As best shown inFIGS. 3 and 4 of the drawings the lobe 211C might be termed the drivinglobe and when the cam roller is permitted to move within the contines ofthe lobe 211C as shown in FIGS. 3 and 4, the drive rollers 132 arebiased into driving engagement with the associated drive channels 163 inthe wheels 33 and 34 under the influence of the springs 170. The lobes211C as indicated in FIGS. 3 and 4 ofthe drawings are sufciently deep sothat cam rollers 206 do not engage the walls of openings 211 but insteaddrive rollers 132 and channels 163 limit the position of rollers 206. Ithowever, the handle 36 is lowered slightly the cam rollers 206 are movedinto the portion of opening 21,1 defined by the lobe 211:1 as clearlyindicated in FIG. 19 of the drawings and this is the normal no driveposition wherein the wheels 33 and 34 are pivoted out of drivingengagement with the drive rollers 132. With the above describedarrangement a slight downward force on the handle 36 from the positionshown in FIG. 4 of the drawings interrupts the drive of wheels 33 and34tand the cams 266 are held in lobes 211e' by the detent action of thelobe configuration. If the operator prefers to terminate the driving ofwheels 33 and 34 by an upward movement of the handle from the positionshown in FIG. 4, this can also be accomplished as shown in FIG. 18 ofthe drawings where the rollers 206 are associated with the lobes 21.1b.

When the power cord is wrapped around the handle 36 including the cordstorage bracket 55 `as described above the weight of this cord may tendto pivot the mower in clockwise direction about the roller 177 as viewedin FIG. 3 of the drawings which is undesirable.- To avoid this, the camrollers 206 may be moved into the lobe 211a of the opening 211 asindicated in FIG. 20 of the drawings whereby the handle assembly 36 isin subtsantially a vertical position and the center of gravity of theentire lawn mower including the power cord is such that no danger oftipping over is involved.` The detent action of lobes 211151 insuresthat the handle, when in the position of FIG. 20, remains there untilmoved by the operator. -An additional advantage of the vertical handleposition is that less storage space for the mower is required. lItshould be appreciated that all positions of the rollers 206 except inlobes 211C are no drive positions.

Sometimes it is necessary to manipulate the lawn mower by lifting itover an obstruction or the like and this is accomplished by pushing downon the handle so `as to lift the ground wheels off the ground wherebythe entire weight of the mower is placed on the roller 177. To this tendthe handle is moved to the no drive position shown in FIG. 19 of thedrawings wherein the handle mounting plates and 11911 engage shoulders311/1 (FIGS. 18 and 19) integrally formed with the frame 311. Theseshoulders insure that the rollers 206 are not subjected to the forcenecessary to raise the wheels 33 and 34 oit the ground to move the mowerover an obstruction. lIn other words, the handle mounting plates 190 and191 engage the shoulders 31h before the rollers 206 engage the ends ofthe openings 211.

On some occasions as when mowing on a hillside and going up a hill itniay'be desirable to provide means to prevent the forward portion Voftherlawnv mower from *airs/isa raising upwardly and'tip'ping back uponitself.` To this end as best shown in FIGS. 2 and '2O ofthe drawingsythere is provided an upstop 214 pivotally mounted to the end plate'31aof the framel about a pivot point 213..

This upstop214 may be moved .into engagement withthe handle mountingplate ltithereby to limit the relative Y upward movement of the handleassembly v3d to the frame f i i v1o For thepurpose of preventing grassor other foreign g matter from entering the wheels 33 and 34"' andspecilically so as not tov interfere with the driving surface 153 andthe drive rollers |132, there is provided for each wheelY a grass shieldl216 which comprises a stationary circular plate adapted to beinterposedl between the end plates'of Y the frame 311 and the wheels33and 34 effectively to close-V the chamber delined between theconcentric sleeves 15% and 1611 as best shown in FIG. -12 of thedrawings. vThese grass shields 216V ar-e eachY provided with anenlarged'l opening 217 Vto accommodate the portion 32h of the shaft 32awith respect to ground wheel 34 and to accommodate the stub shaft- 133with respect tol the'ground wheel 33y The enlarged openings 217 arenecessary to permit pivotal movementV of the ground wheel mount-ingplates 149 and 1S@ when moving the handle 36 to the .four positions 'ldeterminedV by lobes 21-1a,.211b, 2111@ and 211:1; Thel guards I216 arealso provided with a .central opening to accommodate the wheel axles.154. `-As illustrated'they are also provided with an4 integralprojection216a which is receivable in one of the openings 165.'In'FIGS., 3 and 12 of the drawings the projection 216g is disposed inopening 165C butit might also be disposed in either of the openings 165band V16501. 'In additionV guards 216 are' provided with an additional.opening to accommodate-a screw 226 (FlGS. 3 and 12) which secures eachVof theV plates 216 toits associated end plate 31a or 31h. In

FIGS. 3 and l2 of the drawings the screw 220 isk indicated as threadedinto `opening 16'5d but it might also be disposed in either of theopenings y165e or 165e dependingV Y upon the particular height of cutadjustment. It will be understood, from the above description that theopenf ings 15a,'165b and 165C determine the three positions in which theaxles lt'may be disposed. The openings 165:1 and 165e are necessary toaccommodate projection 216a and fastening means 220. ,I

With the arrangement described thus far it will be apparent that foreignmatter couldenter the chamber dened within each of the drivingywheels'ffl' and '34 through. the relatively large openings 217 and tothis end thereV are provided a grass shield 222 for each end of mower 30which shields are best shown in FIGS.V 4, 5, l0,- l2

and 20 of the drawings. These shields each 'comprise a flat plateportion 222e which .is biased against the walls'of the guards 216defining the openings 217. As illustrated in the drawings, each guard216 has aV narrow flange portion 216!) surrounding the opening 217against which liange the flat portion 222e of the associatedV shield 222engages. Alt will beappreciated that the' grass shield 222 must have acentral opening for the shaft portionliZby or the stub shaft 133 as thecase Vmay be. A suitable coiled compressionspring 224 concentric withthe axis of shaft f 32a and engage'able with the C-washer 95 'or yatleastv with some means within thereel bearing supports 89 and 90 biasesthe grass shie1ds'222 into engagement withV the;

flange 21611 surrounding the openings 217 in wheel guards 216 as is bestshown in FIGS; 5 and 10 of the drawings.

To prevent rotation of the grass shield 2224 it isV preferably providedwith a pair of linger projections 2225 which are f Vdisposed one oneitherside of best shown in FIG. 3 ofthe drawings. v v

For the purpose of maintaining the desired tension on the drive chain119 there is provided as best shown in FIG. 6`of the drawings anadjusting screw 225 the end of which is adapted to be received inarecess 226 in the,

one of Y.thestruts 83 as is- -motor mounting bracket 7llb. Preferablythe top chain guard 122 is provided with a projection 122e dening asquare recess 227 for receiving therein a square nut 22d. Upon adjustingthe screw 225 itis apparent that the motor f supporting .arm Vtib willbel pivoted in a clockwise direction as viewed in FIG. 6Vo'f thedrawings about the crossbar 31d which will tend to raise the power unit35 and hence increaseY the tension on .thevchain 119. It will beYappreciated thatunder these conditions 'the fastening means a and7i-ib' must be released so that the supports 7tlg and'tb maybe pivotedunder the action of the adjusting screw 225. TheadjUStingSCreW'225engages the bracket '7de closely adjacent'fthe sprocket d5 which insures,proper adjustment.

To protect the motor 71 and the reduction gearand overload clutchmechanism 72 against the'entrance of water or moisture at the end of thehousing Vwhere the powerrcord l5 and cooling air enter while'stillpermitting the entrance of a' stream oic cooling air for cooling themotor 71', there is provided a motor end'cap 236 (HG. 22) which issuitably, secured to the end of the motor housing 77 remote from gearhousing 7d.. A gasket is disposed in sealed relationship between-thehousing '77 f and end cap 23d. .A suitable gromrnet 232 supported in theend cap 23d provides the waterproof entrance for the y power cord d5;The end of the motor housing 77 associated with end cap 23d is providedwith Va plurality of openings, oneof which, 23.4, is illustrated'in FG.22 of the drawings. In accordance-with the present invention, the endcap 23'@ is provided withrlabyrinth passageway including an air inletopening 235 and a b'afiie 236 which Acauses the air-to` flow firstupwardly and then downwardly as indicated by the arrows in FIG. 23before entering the air inlet openings such as 234 in the motor housing77. A' small opening 237 at thebottom of the* end cap 23d is providedtopermit any water which could possibly cuter v the opening 235 to drainfrom the end cap 2.39 and-not Vfor the lawn mower is provided Vand yetone which has great strength.v V,Simple means are provided for malingthe necessary adjustments as toiheight of cut. V1n addition, a verysimple arrangementis provided for vcausing Y the ground wheels'to bedriven.

While there has been shown'rand described 'a particular embodiment ofthe present invention, it will be apparent to those skilled in the artthat various'changcs and modiiications maybe made without departing fromthe invention in its Vbroader aspects, and it is therefore contemplatedin the appended claims to cover all such changes and modiications asfail within the true spirit and scope :of the present invention. I i pWhat is claimed 4as new and desired to be secured by LettersPatent ofthe United States is:

l. A' reel type lawnrnower comprising a frame of cast aluminum'including a pair of end plates and a tubularportion extending betweensaid end plates and rigidly connected thereto, a steel tube housedwithin said tubular portionrwith the endsrthereo'f embedded in said'endplates,

a pair of members seated against the ends of said tube and, held againstrotation relative to said frame, a tension bolt extending through saidtubeand bearing against the -outer sides of said members, the ends ofsaid tension bolt being eccentrically disposed relative to the axis ofsaid tube,rand a lug in said tube forced by said tension bolt againstthe central portion of said tube.

2. in a reel type lawn mower, a :cast aluminum frame including a pair ofend plates and a tubular portion extending between said end plates andrigidly connected thereto, a cutter bar supported on said tube, saidframe including a steel tube embedded in said tubular portion, a pair ofwasher-like members seated at the ends of said tube, said washer-likemembers having eccentrically disposed yopenings defined therein, meansfor keying said washers to said frame, a bolt extending through saidopenings in said washer-like members and said tube, a nut on one end ofsaid bolt, and a lug secured to the central portion of said bolt andbearing against said tube, whereby upon applying tension to said bolt atransverse bowing force is applied to said tube and cutter bar supportedthereon.

3. In a lawn mower, the combination of a cast frame of aluminum, cuttingmeans rotatably mounted on said frame, said frame comprising a firsttubular steel member and asecond tubular steel member extending parallelwith said rst tubular member and spaced therefrom, said frame alsocomprising a pair of end plates of aluminum cast over the ends of atleast said irst tubular member and mechanically interlocked therewith,and a cutter bar support of aluminum integral with said end plates andcast around said second tubular member and mechanically interlockedtherewith.

4. The lawn mower frame of claim 3 wherein said cutter bar support isformed of aluminum and includes a plurality of integral webs extendingtransversely of the axis of said second steel tube.

5. The lawn mower of claim 3 wherein the interior of one of said tubularsteel members is accessible from either end of said frame.

References Cited by the Examiner UNITED STATES PATENTS 896,998 6/08McGuire 56-294 X 1,907,005 5/ 33 Risser 280-44 2,422,824 6/47 Clausen etal. S10-52 2,424,317 7/47 Jones 310-52 2,671,390 3/ 54 Kinkead 56-2492,689,947 6/54 Weimer 56-26 2,690,637 10/54 Timmins 56-26 2,723,524l11/55 Elliott 56-249 2,730,374 1/56 Rogers et al. 280-44 2,786,321 3/57Lill 56-249 2,861,333 11/58 Morin 24-527 T. GRAHAM CRAVER, PrimaryExaminer.

CARL W. ROBlNSON, ARNOLD RUEGG, Examiners.

1. A REEL TYPE LAWN MOWER COMPRISING A FRAME OF CAST ALUMINUM INCLUDINGA PAIR OF END PLATES AND A TUBULAR PORTION EXTENDING BETWEEN SAID ENDPLATES AND RIGIDLY CONNECTED THERETO, A STEEL TUBE HOUSED WITHIN SAIDTUBULAR PORTION WITH THE ENDS THEREOF EMBEDDED IN SAID END PLATES, APAIR OF MEMBERS SEATED AGAINST THE ENDS OF SAID TUBE AND HELD AGAINSTROTATION RELATIVE TO SAID FRAME, A TENSION BOLT EXTENDING THROUGH SAIDTUBE AND BEARING AGAINST THE OUTER SIDES OF SAID MEMBERS, THE ENDS OFSAID TENSION BOLT BEING ECCENTRICALLY DISPOSED RELATIVE TO THE AXIS OFSAID TUBE, AND A LUG IN SAID TUBE FORCED BY SAID TENSION BOLT AGAINSTTHE CENTRAL PORTION OF SAID TUBE.